The invention relates to a multipole circuit breaker with molded insulating case comprising:
a base plate subdivided by spacers into several juxtaposed compartments for housing the different poles, each pole comprising a breaking module with separable contacts and a trip module, PA1 a cover fixed onto the base plate to close the case, PA1 an operating mechanism, mounted between a pair of support plates, and having a toggle device associated with a connecting spring, and with a tripping hook, PA1 a handle coupled to the mechanism, and passing through an aperture of the cover to be accessible from outside, PA1 a switching bar made of insulating material acting as support for the movable contacts of all the poles, the bar being mechanically coupled to the toggle device and being mounted with limited rotation between the closed position and the open position of the contacts, PA1 a trip bar cooperating with the trip modules of the poles, and with a latch of the tripping hook. PA1 each breaking module is formed by a parallelepipedic monoblock cartridge made of plastic material, housed in the corresponding compartment of the base plate, said cartridge housing at least a stationary contact, an arc extinguishing chamber, and a pair of connecting strips for connection to a terminal and to the trip module of the same pole, PA1 a mechanical actuation module, constituted by the switching bar and mechanism assembly, is securedly united to the cover, PA1 the rotary trip bar is supported by clipping means, arranged on the bottom face of the cover, PA1 and a plurality of recesses and cutouts arranged in the spacers of the base plate to act as first bearing surfaces respectively for the switching bar and trip bar when the first sub-assembly A composed of the base plate with the set of breaking modules and trip modules, is adjoined with the second sub-assembly B formed by the cover on which the mechanical actuation module, trip bar and latch are fitted.
Depending on the type of the customer's electrical installation, protective circuit breakers may be single-pole or multipole with two, three or four poles. Depending on the circuit breaker rating and the type of protection required, certain components or parts, notably the mechanism, switching bar, contact parts, extinguishing chambers, and trip devices moreover have to be suitably adapted. To achieve this a range of circuit breakers requires a multitude of alternative versions. Manufacturing such a range gives rise to assembly problems, as the parts or components to be adapted do not always have the same shapes or structures, and are not easily interchangeable.